Overhead roll-up doors provide resistance to high winds and/or air pressure. These doors typically include a door panel having opposing side edges that engage with, and are vertically guided in, side columns. In order to enhance the door's resistance to high winds and/or air pressure, the opposing side edges of the door panel may include a continuous thickened edge engage the side columns when high winds “impact” the door panel. However, there are at least three major drawbacks to using these known continuous thickened side edges.
For example, these overhead roll-up doors are typically installed in high-traffic areas with the potential to be impacted by objects or vehicles when the door is opening or closing. While many of these doors include features which allow the door panel to disengage when impacted with such a force, when a continuous thickened edge is applied to the opposing side edges of the door panel the opposing edges may become stuck or jammed in the side columns. If the continuous thickened edges become jammed in the side columns, the door panel may not be able to fully disengage from the side columns, increasing the likelihood of damage to the side columns, the door panel, the thickened edges, or other components associated with the door panel, like for example a bottom bar. In addition, if these thickened side edges become stuck or jammed in the side column, the sticking or jamming may prevent the motor from raising the door panel, potentially damaging the motor and preventing any self-repair features of the door panel from working. In order to repair such doors and get the door panel vertically moving again, frequently a portion of the side column must be removed so the continuous thickened edge can be un-jammed and placed back in the path of travel in the side column.
Another problem with the utilization of continuous wind locks is that they typically substantially increase the diameter of the door panel when it is substantially fully wound on the drum in a substantially open position. The larger diameter requires a larger header which may be more costly and consequently may result in a smaller opening.
Still another drawback to using continuous thickened edges is that continuous thickened edges may increase the total weight of the door, creating additional stress on the motor controlling the door as it moves vertically.
In other prior art door designs, in order to enhance the wind lock of the door panel, small knobs or protrusions may be placed proximate opposing edges of the door panel. These knobs or protrusions typically engage a portion of a side column guiding the door, increasing the resistance of the door in response to force from wind or air pressure on the door. However, these knobs or protrusions may offer less resistance than is necessary, and, under extreme forces, like for example high winds or forces imparted by objects impacting the door panel, thereby resulting in such knobs or protrusions breaking away from the door panel, eliminating any wind load resistance benefit they provide. In order to realize the advantages of the knobs and protrusions once they have been broken away, the knobs or protrusions must be replaced on the door panel, requiring that the engaged edge of the panel be exposed by either disengaging the door panel or removing a portion of the side column, rendering the door inoperable during the replacement process.
Therefore, it would be advantageous to design an overhead roll-up door assembly and panel having a wind lock capable of providing necessary wind load resistance while allowing for maximum breakaway-ability if the door panel is impacted by an object.
It would be further advantageous if the wind lock utilized in the door assembly and panel was capable of winding on a drum without a substantially increased diameter, necessitating the use of a larger header, thereby reducing the size of the opening.
It would be further advantageous if the wind lock utilized in the door assembly could be made light weight to reduce strain on any motors used to vertically move the door panel.
The present invention is directed to solving these and other problems.